氮肥运筹对冬小麦第三节间抗倒性能的影响

以烟农19和新麦26两个品种为试验材料,在安徽省蒙城县农业示范场大田条件下,开展了不同氮肥运筹方式对冬小麦第三节间抗倒性能影响的研究,施氮量分别为135 (N1)、180 (N2)、225 (N3)和270 (N4) kg·hm-2,氮肥基追比分别为10∶0 (R1)、7∶3(R2)、5∶5(R3)、3∶7(R4).结果 表明,从开花期到蜡熟期小麦基部第三节间的抗倒性呈降低的趋势,第三节间有倒伏发生的可能.氮肥运筹方式显著影响冬小麦第三节间倒伏的发生,增施氮肥会导致第三节间的抗倒伏性能降低,适当减少基施氮量的比例有利于提高第三节间的抗倒伏能力.另外在施氮量225 kg·hm2及基追比为5:5时第三节间抗倒伏性能最强.第三节间倒伏率与第二节间倒伏率和田间倒伏率呈极显著正相关关系,说明第三节间可以取代第二节间反映田间倒伏情况.纤维素含量/木质素含量与基部节间抗倒伏指数呈极显著负相关关系,可能是决定小麦基部抗倒性的关键指标.     

Improving winter wheat grain yield and water-/nitrogen-use efficiency by optimizing the micro-sprinkling irrigation amount and nitrogen application rate

Available irrigation resources are becoming increasingly scarce in the North China Plain (NCP),and nitrogen-use efficiency of crop production is also relatively low.Thus,it is imperative to improve the water-use efficiency (WUE) and nitrogen fertilizer productivity on the NCP.Here,we conducted a two-year field experiment to explore the effects of different irrigation amounts (S60,60 mm;S90,90 mm;S120,120 mm;S150,150 mm) and nitrogen application rates (150,195 and 240 kg ha~(–1);denoted as N1,N2 and N3,respectively) under micro-sprinkling with water and nitrogen combined on the grain yield(GY),yield components,leaf area index (LAI),flag leaf chlorophyll content,dry matter accumulation (DM),WUE,and nitrogen partial factor productivity (NPFP).The results indicated that the GY and NPFP increased significantly with increasing irrigation amount,but there was no significant difference between S120 and S150;WUE significantly increased first but then decreased with increasing irrigation and S120 achieved the highest WUE.The increase in nitrogen was beneficial to improving the GY and WUE in S60 and S90,while the excessive nitrogen application (N3) significantly reduced the GY and WUE in S120 and S150 compared with those in the N2 treatment.The NPFP significantly decreased with increasing nitrogen rate under the same irrigation treatments.The synchronous increase in spike number (SN) and 1 000-grain weight (TWG)was the main reason for the large increase in GY by micro-sprinkling with increasing irrigation,and the differences in SN and TGW between S120 and S150 were small.Under S60 and S90,the TGW increased with increasing nitrogen application,which enhanced the GY,while N2 achieved the highest TWG in S120 and S150.At the filling stage,the LAI increased with increasing irrigation,and greater amounts of irrigation significantly increased the chlorophyll content in the flag leaf,which was instrumental in increasing DM after anthesis and increasing the TGW.Micro-sprinkling with increased amounts of irrigation or excessive nitrogen application decreased the WUE mainly due to the increase in total water consumption (ET)and the small increase or decrease in GY.Moreover,the increase in irrigation increased the total nitrogen accumulation or contents (TNC) of plants at maturity and reduced the residual nitrate-nitrogen in the soil (SNC),which was conducive to the increase in NPFP,but there was no significant difference in TNC between S120 and S150.Under the same irrigation treatments,an increase in nitrogen application significantly increased the residual SNC and decreased the NPFP.Overall,micro-sprinkling with 120 mm of irrigation and a total nitrogen application of 195 kg ha~(–1) can lead to increases in GY,WUE and NPFP on the NCP.     

微喷水肥一体化氮肥管理对冬小麦产量、品质、氮素积累和利用的影响

为探究冬小麦微喷水肥一体化适宜的氮肥施用方式,于2018—2019年在微喷水肥一体化条件下,以‘济麦22’为材料,设置120(N₁)、210(N₂)和300 kg/hm²(N₃)3个施氮量处理,每个施氮量下设置拔节期一次性追氮(JS)和拔节期、孕穗期、开花期和灌浆期等量分次追氮(4T)2种追氮方式,测定冬小麦产量、蛋白质组分含量、面团品质、氮素积累和土壤硝态氮含量。结果表明：微喷灌条件下,氮肥分施(4T)显著促进冬小麦花后干物质积累,显著提高千粒重,进而显著提高籽粒产量,N₃-4T处理的产量最高,为9 951.2 kg/hm²。在相同追氮方式下,随着施氮量的增加,JS处理显著提高了球蛋白、醇溶蛋白和谷蛋白含量,显著延长了面团稳定时间;4T处理随着施氮量增加,籽粒总蛋白含量无显著变化,清蛋白、醇溶蛋白和谷蛋白含量均呈下降趋势,高氮处理下(N₃)湿面筋含量和面团形成时间均显著下降。在相同施氮量下,相较于JS处理,4T处理可显著提高花后干物...     

不同氮钾肥施用方法对水稻产量及抗倒伏性的影响

水稻倒伏常发生于籽粒灌浆中后期,是高产、稳产、优质生产的主要限制因素之一。试验选用寒地超级稻品种松粳9号,研究不同氮钾肥施用方法对水稻产量性状及茎秆抗倒特性的影响,为寒地水稻超高产抗倒栽培技术的建立提供理论依据。结果表明,施氮量为90 kg·hm-2时,增加生育前期氮肥施用量有利于提高单株穗数、每穗粒数和单株粒重,但施氮量为135 kg·hm-2时,减少生育前期氮肥施用量,而提高生育后期氮肥施用量更有利于提高单株穗数、每穗粒数和单株粒重;在同等施氮量条件下,增加生育前期氮肥施用量可极显著增加第1和第2节间长度,并降低茎秆抗折力,尤其是施氮量高时这种影响更大;增加氮肥施用量时,相应增加钾肥施用量和减少生育前期氮肥施用量将有利于提高茎秆抗倒特性;增加生育后期氮肥施用量明显提高茎秆全氮含量,而增加生育前期氮肥施用量有利于促进水稻植株钾的吸收和积累,提高茎秆钾含量;茎秆氮含量与节间长度呈显著或极显著正相关,与抗折力呈负相关;茎秆钾含量与节间长度呈显著负相关,与抗折力呈极显著正相关。     

Yield and water use responses of winter wheat to irrigation and nitrogen application in the North China Plain

With increasing water shortage resources and extravagant nitrogen application, there is an urgent need to optimize irrigation regimes and nitrogen management for winter wheat(Triticum aestivum L.) in the North China Plain(NCP). A 4-year field experiment was conducted to evaluate the effect of three irrigation levels(W1, irrigation once at jointing stage; W2, irrigation once at jointing and once at heading stage; W3, irrigation once at jointing, once at heading, and once at filling stage; 60 mm each irrigation) and four N fertilizer rates(N0, 0; N1, 100 kg N ha~(-1); N2, 200 kg N ha~(-1); N3, 300 kg N ha~(-1)) on wheat yield, water use efficiency, fertilizer agronomic efficiency, and economic benefits. The results showed that wheat yield under W2 condition was similar to that under W3, and greater than that under W1 at the same nitrogen level. Yield with the N1 treatment was higher than that with the N0 treatment, but not significantly different from that obtained with the N2 and N3 treatments. The W2 N1 treatment resulted in the highest water use and fertilizer agronomic efficiencies. Compared with local traditional practice(W3 N3), the net income and output-input ratio of W2 N1 were greater by 12.3 and 19.5%, respectively. These findings suggest that two irrigation events of 60 mm each coupled with application of 100 kg N ha~(–1) is sufficient to provide a high wheat yield during drought growing seasons in the NCP.     

播种量与氮肥运筹对直播杂交籼稻抗倒伏潜力及产量的影响

以早熟杂交稻组合446A/518为试验材料,研究播种量和氮肥运筹方式对直播水稻抗倒伏能力及产量的影响,并探讨茎秆理化性质与植株倒伏指数之间的关系.结果表明,播种量和氮肥运筹方式对水稻节间茎秆理化性质、抗倒伏能力及产量均有显著影响.随着播种量的增加,植株的抗倒伏能力有一定的降低,而氮肥运筹方式对水稻节间倒伏指数的影响差异较大.当播种量小于22.5 kg/hm2时,穗肥比例的增加会加大植株倒伏的风险,而当播种量增加到30.0 kg/hm2时,增加穗肥比例有利于提高植株的抗倒伏能力,可能与其基部节间变短、扁平率及空腔面积变小、折断弯矩变大、纤维素和木质素含量较高有关.相关分析表明,在不同播种量和氮肥运筹方式下水稻茎秆理化性质与植株的抗倒伏能力显著或极显著相关.总之,在播种量为22.5 kg/hm2,底肥、蘖肥、穗肥比例为5∶2∶3时直播稻的产量相对较高,且抗倒伏能力较好,为本试验的最佳处理.     

基于力学模型的小麦腊熟期倒伏的风速研究

随着小麦产量的提高袁其倒伏的可能性也增大。因此,解决小麦的倒伏问题对提高小麦产量具有重要意义。将腊熟期小麦茎秆简化为刚/弹性材料,研究了腊熟期小麦茎秆在风载作用下应力变化的基本规律袁运用振动理论建立了小麦单茎穗重在风载作用下的抗倒伏力学模型遥最后,利用2013年的试验数据,基于该模型计算出了周麦18茎秆和矮抗58茎秆的抗倒伏风速,计算结果与已有文献数据较吻合,表明该模型可为研究小麦的抗倒伏提供一定的理论依据。     

微喷水肥一体化对冬小麦产量和水分利用效率的影响

为探明不同微喷灌施氮方式对冬小麦产量及水分利用效率的影响,以‘济麦22’为材料,在底施纯氮105kg/hm~2条件下,2016年春季设置追施纯氮45(N1)、90(N2)和135kg/hm~2(N3),每个追氮量采用微喷灌拔节期一次性追施(JS)和分别在拔节、孕穗、开花和灌浆期4次等量追施(4T)2种方式,测定冬小麦的产量和水分利用效率。结果表明:1)微喷灌条件下,随施氮量的增加,冬小麦产量先增加后降低,以N2处理产量最高;相同施氮量下,分次施氮处理产量显著高于拔节期一次性施氮,产量的增加主要由于显著提高千粒重;2)拔节期一次性施氮提高冬小麦开花期群体叶面积指数,而分次施氮处理灌浆期的叶面积指数显著高于拔节期一次性施氮,相同施氮量下分次施氮延缓灌浆中后期旗叶的衰老,从而有利于花后干物质积累和粒重的提高,但过多施氮导致粒重下降,总干物质积累量减少;3)不同施氮量处理间水分利用效率以N2处理最高,相同施氮量下分次施氮处理水分利用效率显著高于拔节期一次性施氮处理。综上所述,与拔节期一次性施氮相比,微喷灌采用分次施氮显著提高冬小麦的产量和水分利用效率,微喷水肥一体化N2处理下分次施氮为最佳的高产高效氮肥运筹模式。     

氮肥优化管理对稻花香抗倒伏能力的影响

优质水稻品种稻花香2号易倒伏,通过改善栽培措施提高其抗倒伏能力具有重要意义。设置习惯施肥、氮肥综合管理和控释掺混肥等处理,研究氮肥管理模式对稻花香2号抗倒伏能力影响。结果表明,与习惯施肥相比,氮肥综合管理处理增加茎秆含钾量,显著提高水稻茎秆抗折力,水稻田间倒伏较少或未倒伏,而习惯施肥处理倒伏比例为4.5%~8.7%(P0.05);氮肥综合管理和控释掺混肥处理比习惯施肥水稻产量提高7.0%和9.2%(P0.05);施用控释掺混肥处理水稻基部节间长度、基部第二节间充实度和茎秆抗折力等与氮肥综合管理处理无显著差异,但田间倒伏比例显著高于氮肥综合管理和习惯施肥,原因是施用控释肥掺混肥处理在整地时控释肥漂浮导致肥料分布不匀。氮肥综合管理可提高稻花香抗倒伏能力,提高水稻产量及稳产性。     

Late sowing enhances lodging resistance of wheat plants by improving the biosynthesis and accumulation of lignin and cellulose

Delayed sowing mitigates lodging in wheat. However, the mechanism underlying the enhanced lodging resistance in wheat has yet to be fully elucidated. Field experiments were conducted to investigate the effects of sowing date on lignin and cellulose metabolism, stem morphological characteristics, lodging resistance, and grain yield. Seeds of Tainong 18, a winter wheat variety, were sown on October 8 (normal sowing) and October 22 (late sowing) during both of the 2015–2016 and 2016–2017 growing seasons. The results showed that late sowing enhanced the lodging resistance of wheat by improving the biosynthesis and accumulation of lignin and cellulose. Under late sowing, the expression levels of key genes (TaPAL, TaCCR, TaCOMT, TaCAD, and TaCesA1, 3, 4, 7, and 8) and enzyme activities (TaPAL and TaCAD) related to lignin and cellulose biosynthesis peaked 4–12 days earlier, and except for the TaPAL, TaCCR, and TaCesA1 genes and TaPAL, in most cases they were significantly higher than under normal sowing. As a result, lignin and cellulose accumulated quickly during the stem elongation stage. The mean and maximum accumulation rates of lignin and cellulose increased, the maximum accumulation contents of lignin and cellulose were higher, and the cellulose accumulation duration was prolonged. Consequently, the lignin/cellulose ratio and lignin content were increased from 0 day and the cellulose content was increased from 11 days after jointing onward. Our main finding is that the improved biosynthesis and accumulation of lignin and cellulose were responsible for increasing the stem-filling degree, breaking strength, and lodging resistance. The major functional genes enhancing lodging resistance in wheat that are induced by delayed sowing need to be determined.     

Coupling effects of irrigation and nitrogen fertilization on grain protein and starch quality of strong-gluten winter wheat

Effects of irrigation and nitrogen fertilization on the grain yield, protein composition, protein quality, starch composition and starch pasting properties of a strong-gluten winter wheat were investigated in a high fertility field. Compared with non-irrigation treatment, grain yields under irrigation treatments were significantly increased, but the content of grain protein, monomeric protein and flour wet gluten was reduced. There were no significant differences in the above parameters between the irrigation treatments. Nitrogen application could significantly increase grain yield under low irrigation frequency (W₀ and W₁), while the neglected effect on yield was observed with high irrigation frequency (W₂ and W₃). With the increase of irrigation frequency, the glutenin content leveled off, but the changes of glutenin composition were not uniform, in which the soluble glutenin content was increased, while the insoluble glutenin content and polymerization index (the ratio of insoluble glutenin to total glutenin) were reduced. Both dough development time and stability time became shorter with the increased irrigation frequency. Nitrogen application improved the content of all grain protein fractions and grain quality, in which the increased degree in non-gluten protein (albumin and globulin) was higher than gluten protein (gliadin and glutenin), and the increased degree in soluble glutenin was found higher than that of insoluble glutenin. The interactive effects of irrigation and nitrogen on starch composition were significant. Starch content and amylopectin content was increased as irrigation frequency added in non-nitrogen treatment. Compared to non-irrigation treatment, irrigation significantly increased the starch content and the amylopectin content in nitrogen application treatment, but the starch and amylopectin content had no significant difference between irrigation treatments. Amylose content and the ratio of amylose to amylopectin were reduced while RVA indexes (peak viscosity, breakdown, final viscosity and setback) were increased as irrigation frequency was increased. Nitrogen application significantly improved the amylopectin content and decreased the amylose content in lower frequency irrigation, while the amylopectin content was decreased and the amylose content was enhanced by nitrogen application in higher frequency irrigations. __________ Translated from Plant Nutrition and Fertilizer Science, 2007, 13(3): 361–367 [译自: 植物营养与肥料学报]     

播期和密度对滴灌冬小麦群体结构与抗倒特性的影响

以新冬22(少穗型)和邯郸5316(多穗型)为供试材料,采用裂区田间试验设计,主区为3个播期:9月23日(B1)、10月4日(B2)和10月15日(B3);副区为4个播种密度:315万株·hm^-2(M1)、510万株·hm^-2(M2)、705万株·hm^-2(M3)、900万株·hm^-2(M4),研究不同播期和密度对滴灌冬小麦群体动态和抗倒特性的影响。结果表明:(1)滴灌冬小麦生育期随播期推迟而缩短,B3处理的新冬22和邯郸5316的生育期较B2处理缩短11 d,较B1处理缩短22 d;密度对生育进程影响较小。(2)群体大小和叶面积指数(LAI)随密度增加而增加,随播期推迟而减小;晚播群体在生育后期总茎数有追赶正常播期处理的趋势;同一密度下B2处理和同一播期下M2或M3处理的群体大小和叶面积动态随生育进程变化最小,表现出较好的叶片调节功能。(3)随播种密度增加,滴灌冬小麦基部节间和重心高度增加,基部直径、机械强度和抗倒指数下降;随播期延迟,茎秆基部节间变短,重心高度下降,直径增大,机械强度和抗倒指数增加;密度对茎秆性状的影响大于播期;在实际生产中,充分发挥密度和播期的互作效应,适当增加晚播处理的密度,能优化个体生长,保证高产。(4)B2处理的平均产量较B1、B3处理分别提高8.09%~17.52%和16.01%~21.07%,新冬22和邯郸5316分别在B2M3和B2M2处理中产量最高,分别达8 541.04 kg·hm^-2和9 218.08 kg·hm^-2。(5)从群个体生长的角度上看,新冬22对密度反应更敏感,邯郸5316对播期反应更敏感;说明生产中少穗型品种应注重合理密度前提下调节播期,而多穗型品种应注重适当播期前提下调节密度,以充分发挥品种的增产潜力。     

Effects of uniconazole with or without micronutrient on the lignin biosynthesis,lodging resistance,and winter wheat production in semiarid regions

Lodging stress results in grain yield and quality reduction in wheat. Uniconazole, a potential plant growth regulator significantly enhances lignin biosynthesis and thus provides mechanical strength to plants in order to cope with lodging stress. A field study was conducted during the 2015–2016 and 2016–2017 growing seasons, to investigate the effects of uniconazole sole application or with micronutrient on the lignin biosynthesis, lodging resistance, and production of winter wheat. In the first experiment, uniconazole at concentrations of 0(CK), 15(US1), 30(US2), and 45(US3) mg L~(-1)was applied as sole seed soaking, while in the second experiment with manganese(Mn) at concentration of 0.06 g L~(-1)Mn, 0.06 g L~(-1)Mn+ 15 mg L~(-1)uniconazole(UMS1), 0.06 g L~(-1)Mn+30 mg L~(-1)uniconazole(UMS2), and 0.06 g L~(-1)Mn+45 mg L~(-1)uniconazole(UMS3), respectively. Uniconazole sole application or with micronutrient significantly increased the lignin content by improving the lignin-related enzyme activities of phenylalanine ammonia-lyase, cinnamyl alcohol dehydrogenase, tyrosine ammonialyase, and peroxidase, ameliorating basal internode characteristics, and breaking strength. The spike length, spike diameter, spikes/plant, weight/spike, yield/spike, and grain yield increased and then decreased with uniconazole application at a higher concentration, where their maximum values were recorded with UMS2 and US2 treatments. The lignin accumulation was positively correlated with lignin-related enzyme activities and breaking strength while, negatively correlated with lodging rate. Uniconazole significantly improved the lignin biosynthesis, lodging resistance, and grain yield of winter wheat and the treatments which showed the greatest effects were uniconazole seed soaking with micronutrient at a concentration of 30 mg L~(-1)and 0.06 g L~(-1), and uniconazole sole seed soaking at a concentration of 30 mg L~(-1).     

Lodging resistance and yield potential of winter wheat: effect of planting density and genotype

Improved lodging resistance is important for achieving high yield in irrigated environments. This study was conducted to determine genotypic variation in lodging resistance and related morphological traits among winter wheat cultivars planted at two densities, and to identify key traits associated with lodging resistance. Lodging performance of 28 genotypes, including 24 released cultivars and four advanced lines, was evaluated at 250 plants per square meter and 500 plants per square meter in Shandong province during the 2008–2009 and 2009–2010 crop seasons. At the higher density, the average grain yield was 2.6% higher, even though lodging score rose by as much as 136%. The higher planting density increased lodging through increased leaf area index (LAI), plant height, center of gravity and length of basal internodes, and reduced grain weight per spike and diameter of the lower two stem internodes. LAI, center of gravity and diameter of first internodes, as the important indicators for lodging resistance, were significantly correlated with lodging score, with R= 0.62, 0.59 and −0.52 (P<0.01), respectively. Plant pushing resistance was significantly associated with diameter and length of the first internodes (R = 0.71–0.77, P<0.01), indicating it could be used to assess the strength of the lower stem. Higher planting density could be used to select genotypes with lodging resistance in irrigated environments. Cultivars carrying high plant density tolerance and high yield potential, such as Jimai 22 and Liangxing 66, were recommended as leading cultivars for production as well as elite crossing parents for further increasing yield potential in the Yellow and Huai Valleys Winter Wheat Zone in China.     

不同蘖穗肥施氮量对水稻根系、抗倒性及产量性状影响

以寒地穗数型中晚熟高产品种松粳6号和穗重型晚熟超级稻品种松粳9号为试验材料,在统一施氮量不同施肥方式条件下,比较分析水稻根系形态和活力、茎秆抗倒性状等动态变化,以期为寒地水稻施肥方法提供理论依据。结果表明,在生育前期,随氮肥量增加,根系体积、长度、干重和伤流液量也随之增加。在生育后期,随穗肥施氮量减少,根系体积、长度、干重和伤流液量均先增后减。因此,后期施用较多肥料不利保持根系形态和活力。随基蘖肥施氮量增加,穗肥施氮量减少,第一节间长度呈增加趋势,第二节间长度先升后降,第一节间和第二节间茎秆直径与抗折力均先升后降,产量上也表现相同趋势。因此,适宜基蘖肥和穗肥比例可显著提高水稻根系活力和茎秆抗折力,提高水稻产量。     

Nitrate leaching of winter wheat grown in lysimeters as affected by fertilizers and irrigation on the North China Plain

Proper application of nitrogen(N) fertilizers and irrigation management are important production practices that can reduce nitrate leaching into groundwater and improve the N use efficiency(NUE). A lysimeter/rain shelter facility was used to study effects of the rate of N fertilization, type of N fertilizer, and irrigation level on key aspects of winter wheat production over three growing seasons(response variables were nitrate transport, N leaching, and NUE). Results indicated that nitrate concentration in the soil profile and N leaching increased with the rate of N fertilization. At the end of the third season, nitrate concentration in the top 0–75 cm layer of soil was higher with manure treatment while urea treatments resulted in higher concentrations in the 100–200 cm layer. With normal irrigation, 3.4 to 15.3% of N from applied fertilizer was leached from the soil, yet no leaching occurred under a stress irrigation treatment. The manure treatment experienced less N leaching than the urea treatment in all cases except for the 180 kg N ha-1 rate in 2011–2012(season 3). In terms of grain yield(GY), dry matter(DM) or NUE parameters, values for the manure treatment were lower than for the urea treatment in 2009–2010(season 1), yet were otherwise higher for urea treatment in season 3. GY and crop nitrogen uptake(NU) were elevated when the rate of N fertilizer increased, while the NUE decreased; GY, DM, and NU increased with the amount of irrigation. Data indicated that reduced rates of N fertilization combined with increased manure application and proper irrigation management can lower nitrate levels in the subsoil and reduce potential N leaching into groundwater.     

不同氮肥与矿化度水平微咸水喷灌对冬小麦光合特征及产量的影响

为寻求合理的微咸水利用方式,揭示微咸水喷灌下作物生理生长响应机理,在河北低平原地区开展了冬小麦微咸水喷灌试验,研究了225 kg·hm-2施氮量条件下不同矿化度(2、3 g·L-1)微咸水灌溉和不同施氮量条件(高氮275 kg·hm-2,中氮225 kg·hm-2,低氮175 kg·hm-2)下2 g·L-1矿化度微咸水喷灌对冬小麦光合特性、生长和产量的影响.结果 表明,与淡水喷灌相比,采用矿化度3 g·L-1微咸水喷灌会导致冬小麦叶片蒸腾速率(Tr)、气孔导度(Gs)和净光合速率(Pn)显著下降,但叶片水分利用效率提高了37.0％～106.8％;2 g·L-1微咸水喷灌高氮和中氮处理的Gs、Pn与淡水喷灌无显著差异,且拔节期高氮处理的叶片Pn略高于淡水喷灌处理5.0％.2 g·L-1微咸水喷灌对冬小麦的叶面积指数和株高影响不显著,3 g·L-1矿化度微咸水喷灌对冬小麦的叶面积指数和群体密度造成不利影响.2 g·L-1微咸水喷灌3个处理冬小麦产量与淡水喷灌处理均无显著差异,但3 g·L-1矿化度处理冬小麦平均产量比淡水喷灌处理显著降低了25.9％.综上所述,矿化度不大于2 g·L-1的咸淡混合水喷灌适用于河北低平原地区冬小麦田间灌溉,添加适量氮肥会促进作物产量的增加.     

冬前镇压和灌溉对冬小麦植株形态和产量的影响

为明确冬前镇压和灌溉对山东省冬小麦生长发育的影响,在2016—2017年小麦生长季,以‘济麦22’为材料,利用大田随机区组试验,分析冬前镇压+灌溉(C+I)、单独灌溉(I)和单独镇压(C)处理对冬小麦植株形态和产量的影响。结果表明,1)与对照(常规种植管理,CK)相比,冬前镇压+灌溉、单独灌溉或镇压都可提高分蘖数、分蘖成穗率和成熟期株高,其中镇压+灌溉处理提高值最大,其次是单独镇压或灌溉处理;2)冬前镇压+灌溉、单独镇压和单独灌溉处理均可降低灌浆期小麦基部第一和二节间长度,增加其比茎重、茎粗以及壁厚,镇压+灌溉处理作用最大,其次是单独镇压和灌溉处理;3)冬前镇压+灌溉、单独灌溉和镇压处理可降低小麦花前贮藏物质的转运量、转移率以及对籽粒的贡献率,却可显著提高花后干物质的积累、转运量、转运率及其对籽粒的贡献率,其中冬前镇压+灌溉处理对物质转运影响最大;4)冬前镇压+灌溉、单独灌溉和镇压处理显著提高小麦单位面积穗数、产量和收获指数,其中最大值出现在镇压+灌溉处理,其次是灌溉和镇压处理。本研究表明,镇压+灌溉(C+I)或单独灌溉(I)或镇压(C)都可以促进小麦生长,提高小麦抗倒伏性和最终产量,其中镇压和灌溉相结合作用要大于单独措施,所以山东省小麦生产中冬前镇压+灌溉措施最佳,但即使在无灌溉条件下,镇压措施仍有利于小麦生产。     

泾惠渠灌区不同水氮供应对冬小麦氮素吸收运转的影响

【目的】研究泾惠渠灌区不同水氮供应对冬小麦植株氮素吸收运转的影响,为泾惠渠灌区提供合理的灌水施肥运筹方式。【方法】在泾惠渠灌区,通过田间小区试验研究不同灌水(W_(90)和W_(120),即灌水定额为90和120mm)和施氮(底肥60和120kg/hm~2,追肥0,60和120kg/hm~2,即施氮的底追肥处理组合为N_(60/0),N_(60/60),N_(60/120);N_(120/0),N_(120/60),N_(120/120))对冬小麦籽粒产量、各部位氮素积累量、氮素利用效率等的影响。【结果】除净积累量对籽粒氮的贡献率及氮素收获指数外,灌水和施氮对冬小麦籽粒产量、各器官氮素积累量、氮素转移量、氮素利用效率、氮肥农学利用效率均有显著影响。低水处理(W_(90))的籽粒产量、氮素积累量、氮肥农学利用效率显著高于高水处理(W120),其中产量增幅为4.88%~7.44%,植株氮素积累量增幅为6.15%~18.66%,氮肥农学利用效率增幅为19.48%~35.94%。随施氮量的增加,冬小麦籽粒产量、氮素积累量均呈显著增长趋势,其中籽粒产量表现为N_(0/0)(5 653.68kg/hm~2)N_(60/0)(6 777.71kg/hm~2)N_(60/60),N_(120/0)(7 165.63kg/hm~2)N_(60/120),N_(120/60)(7 376.92kg/hm~2)N_(120/120)(7 659.88kg/hm~2);氮素积累量表现为N_(0/0)(188.97kg/hm~2)N_(60/0)(229.49kg/hm~2)N_(60/60),N_(120/0)(275.23kg/hm~2)N_(60/120),N_(120/60)(310.00kg/hm~2)N_(120/120)(327.40kg/hm~2);当施氮量过高时,继续增加施氮量对冬小麦籽粒产量和氮素积累量的调节作用不显著。总施氮量相同的条件下,适当提高追肥的施氮比例,有利于提高产量、各器官氮素积累量及各营养器官氮素转移量,其中N_(60/60)与N_(120/0)处理相比,W_(90)和W_(120)灌水水平下籽粒产量分别提高3.92%和4.44%,各器官氮素积累量提高11.43%~27.99%,各营养器官转移量提高18.37%~71.81%;N_(60/120)与N_(120/60)处理相比,各营养器官转移量提高15.06%~39.63%。【结论】综合考虑籽粒产量、氮肥农学利用效率和氮素利用效率等因素,灌水定额为90mm、底肥施氮量60kg/hm~2、追肥施氮量120kg/hm~2,即W_(90)N_(60/120)为本试验条件下泾惠渠灌区冬小麦的最佳水氮组合。     

施氮量对新疆滴灌冬小麦冠层结构及其小气候特征的影响

为明确不同施氮量对新疆冬小麦冠层结构特征及其群体内部光、温变化的影响,于2013—2015年连续2个冬小麦生长周期,在大田滴灌条件下,采用单因素随机区组试验设计,共设置了0(N_0),94.5(N_1),180(N_2),240(N_3),300(N_4)和360kg/hm~2(N_5)6个施氮肥处理,研究了施氮量对冬小麦茎型特征,叶垂直分布及其形态特征,冠层光、温变化规律的影响。结果表明:与N_0处理相比,增施氮肥冬小麦叶片的长、宽及叶片总面积均显著增加。随着施氮量的增加,各叶层LAI、各节间长度和节间粗度均呈"先增后减"的趋势,株高变幅为71.83~85.88cm(2014年)和70.56~85.18cm(2015年);冠层中、下部的透光率和冠层温度均呈"先降后增"的趋势。各处理冠层温度日变化呈"凸"型曲线,均在15:00左右达到峰值,其值以N_3处理最低。2年试验产量均以N_3处理最高,为8 653.22(2013年)和8 415.20kg/hm~2(2014年),分别较同年N_0、N_1、N_2、N_4和N_5处理增产68.01%、32.39%、17.92%、5.34%、10.69%和67.39%、30.81%、19.31%、4.20%、11.49%。本试验条件下,施氮量控制在240kg/hm~2左右,滴灌冬小麦叶型、株型特征良好,冠层光、温适宜,有利于获得高产。